During 22-24 Sep, Monsoon trough lies across the upper North and the Northeast of Thailand to the lower pressure cell over Laos so Likely the North and the Northeast have increasing rain and isolated heavy rain while the southwest monsoon remains to cover the Andaman Sea, the South and the Gulf of Thailand.
During 25-28 Sep, the upper of Thailand have decreasing rain as because Monsoon trough will weaken while the southwest monsoon overs the Andaman Sea, the South and the Gulf of Thailand will stronger so the lower Central, the East and the South likely have more rain and isolated heavy rain.
After Tropical depression “VAMCO” cover Thailand during 15-17 Sep made widespread rain and heavy rain around the lower Northeast and the East, and some areas of the East had flood (Cholburi, Rayong, Chantaburi, Trad province) and causing the increasing of water in reservoirs of the East. But the North and the Central had little affected from the storm.